In the D.C. public schools, where declining student enrollment has long been the rule, Strong John Thomson Elementary in downtown Washington has defied the odds and increased its student population by 20 percent.

It helps that Thomson has some assets to boast that most city schools don't: a renovated building completed in January with a gymnasium and two indoor playgrounds, Chinese language classes and a school culture that emphasizes such values as tolerance and personal responsibility.

But Thomson is different in another way. The school's principal and parents formed a marketing committee to aggressively recruit students. The team worked feverishly this spring, sending out fliers to Chinese nonprofit and business organizations, posting glowing messages on e-mail discussion groups and holding several open houses. All the promotion was done in three languages: English, Spanish and Chinese.

"We really made a conscious effort," said Principal Gladys Camp, who saw enrollment grow from 287 students to about 345 this year. "We wanted to make sure that our enrollment didn't drop."

One of the new enrollees is 5-year-old Hunter, the son of Kathleen Finn, an independent financial consultant. Finn considered private school, but her son was wait-listed, and he wasn't selected for two public school lotteries. She eventually selected Thomson after learning about it through an e-mail promoting the school's open house.

"I didn't know about it," Finn said. "And then I came. The building is gorgeous, and I met the principal, and she seemed to really care about what was going on here."

In the numbers game of student enrollment, where teachers are assigned to schools or cut from them based largely on the number of students, the Thomson team decided to compete for students who might otherwise choose to attend schools outside the traditional system.

In doing so, the school took a page from its charter and private school counterparts, an approach endorsed by Superintendent Clifford B. Janey, who admits that the competitive landscape has pushed the traditional system to do things differently.

"It's increasingly important for principals to see how they can effectively reach out to other markets," Janey said.

Charlotte Bensaada, 34, who spent two years researching D.C. public schools for her 4-year-old daughter Dahbia, said Thomson stood out because of the principal. Camp was known to spend hours with parents of potential students, and she is hands-on with the children, even teaching a guitar class.

"The number one thing she did was flat-out make herself available," said Bensaada, who lives in Brookland. "If I said I want to come and see the school, she said, 'Okay, I can be available at this time -- when do you want to come?' "

Francisco Millet, a regional superintendent, encouraged Camp and other principals to go after students instead of waiting to see who comes in the door. "I think we're learning lessons from the charter schools," Millet said. "They'll literally stand outside our schools and hand out brochures on back-to-school night. We're starting to use some of their methods for getting the word out on our schools."

Despite those efforts, overall enrollment in traditional public schools could decline again this year. The initial 2006 enrollment reported by the school system is 56,787 students, compared with the 2005 verified enrollment of 57,486. The preliminary figure, a one-day snapshot in early October, is being audited by a firm working for the State Education Office. A final report will be released in January.

Meanwhile, charter school enrollment appears to have increased this school year, according to initial figures. Compared with the 2005 verified charter school enrollment of 17,419 students, the city's 55 charter schools reported having 20,058 students this year. The verified numbers for charter schools will also be released in January.

Efforts by such schools as Thomson might buck the downward trend, but the overall enrollment figures are one signal that many parents lack faith in the city's traditional public school system.

The amount of city funds each charter school receives during the year depends on its enrollment. Traditional public school officials use the number of students in each school as a guide to reassigning teachers. Since September, 161 teachers have been transferred, according to school system spokesman John C. White. Thomson started the school year without a permanent first-grade teacher because the slots were based on last year's enrollment, but the school eventually gained five positions because of its growth, officials said.

Named after a 19th-century educator who taught at a private school at the same site, at 12th and L streets NW, Thomson is ethnically diverse, with about an equal number of black and Hispanic students, 139 and 130, respectively, and 69 Asian students. In a reflection of the school's growth, the school's Chinese teacher, Qinghua Wong, now works full time and teaches pre-kindergarten through second grade. Last year, she was part time and taught only second grade.

In a lesson last week, Wong led her class of 24 kindergarten students in a song about body parts as they pointed to their heads and eyes and shoulders. Her brightly colored first-floor classroom has posters of letters and numbers, and every child has a wooden cubby that looks like a mini-locker.

In addition to bringing in new students, the marketing campaign also won involved parents for the school. Thomson doesn't have a school Web site, so Bensaada, the Brookland parent, volunteered to work on one in addition to creating a parent survey so the school can tap parent strengths for volunteer work.

LaDonna Pavetti, a Capitol Hill parent who led the marketing committee in the spring, first saw Thomson when it was temporarily located on G Street in Northeast for 3 1/2 years before moving into the new building this year.

She remembered thinking that the temporary location was dingy, but "there was something about the students," she said -- things like the children saying hello to her as she walked in the hallways.

She also was impressed that Camp spent hours with her and her partner, Mary Fran Miklitsch, on a tour of the school. The couple adopted two children from China, Catherine and ZhenHua, both 7, who are now in second grade at Thomson.

Pavetti said that when she tells friends about all the programs Thomson offers, "Is it a charter school?" is their first question.

"I think a lot of people look at D.C. public schools as a blanket and assume there's lots of problems -- and there are," Pavetti said. "But I felt like this was an undiscovered gem."